The explosion of new information about the human genetic code can be confusing. Up to one third of providers misinterpret genetic risk studies that are conducted on their patients.1 Kenneth Offit, M.D., Ph.D., offers a reference that effectively presents a broad range of information on genetics and cancer for the family physician and anyone engaged in genetic counseling.

Five to 10 percent of cancers may be attributed to a risk carried by a single altered gene. The information bonanza of the human genome project has outpaced science's understanding of genetic risk. Family physicians are on the front lines of this molecular genetics revolution. In their desire to implement cancer prevention strategies, they must be cautious in their use of tests that determine a patient's hereditary predisposition to cancer. Equally important, family physicians need to counsel patients with negative genetic screening and encourage them to follow the American Cancer Society's guidelines for the general population.2

Dr. Offit is chief of clinical genetic services at Memorial Sloan Kettering Cancer Center, New York City, and one of the world's leading figures in clinical cancer genetics. This textbook demonstrates that Dr. Offit is a researcher anchored in patient care and blessed with a gift for clear, concise writing. Throughout the textbook, case examples emphasize principles over details. One example is a discussion of the difference between disease risk genetics such as the risk for breast cancer (BRCA 1) and intra-tumor mutations (CERB-2), which can predict the behavior of individual tumors.

The first three chapters update the reader on clinical cancer genetics and basic scientific concepts. The next two chapters review the most prevalent syndromes of cancer genetic predisposition. Subsequent chapters address the use of quantitative methods in risk counseling, genetic testing methodology, reproductive risk counseling and the special psychosocial, ethical and legal challenges in clinical cancer genetics.

Three appendixes are provided. The first appendix is a table of inherited disorders related to cancer and the genetic locus, if known. The second is an extensive list of resources and services for patients and physicians seeking more information. The third offers familial risk calculations in families with breast and ovarian cancer. Along with the text, figures and tables elucidate complicated issues with useful comparisons, such as an epidemiologic analysis, pedigree analysis, motor vehicle accidents, lightening strikes and drownings. A foreword written by the Director of the National Cancer Institute further validates the book's scientific authenticity.

Dr. Offit's book will be a valuable reference to anyone participating in cancer risk counseling and genetic testing. Dr. Offit makes the point that just as a family physician often defers ordering a chest radiograph and treats pneumonia on the basis of the physical examination, inherited risk will often be managed on the basis of family history without a DNA analysis. The family physician's role in verifying family history is emphasized.

Any patient requesting DNA testing faces issues of fear, anxiety, family strife and discrimination balanced by a desire for targeted surveillance and effective management strategies from their family physician. Clinical Cancer Genetics is a timely review of common genetic issues and elucidates the promise and limitations of cancer genetics.